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Bendix 1200 wiring

AviatorJ

Well Known Member
I have a set of Bendix 1200 magnetos I'm wiring up to my ACS ignition switch. I used 18 ga shielded wire between the post on the Mags and the starter switch. I followed the ACS and VPX instructions which had me connect the shielding to the ACS switch ground. So the shielding is grounded no matter what.

On the Bendix side I just crimped on connectors which I'm guessing crimped the shielding in with the wire, because no matter what the switch position is measuring from the connected posts they're both showing grounded. Easy fix but wanted to ensure I'm wiring the Bendix side correctly before I push on.

My assumption is I don't ground the shielding on the Bendix side. So do I just need to strip the wiring enough that no shielding will get crimped in with the connector? Then do I just connect to the post on the back of the magneto?

To test I want to make sure I'm crystal clear on what should be expected with the ACS in the various positions and measuring between the connected magneto post and the airframe.

Off - Both mags should be grounded
Left - The left mag should show open and the right grounded
Right - The right mag should show open and the left grounded
Both - All mags should show open
Start - Left mag open and right grounded
 
Learned these connections are called P-Leads, with different types where some are grounded on both ends, some aren?t. Also learned different ways to do this with toggles to reduce the risk of having hot mags with a failed ground point. I also found that to test I need to disconnect them from the magneto plead post.

http://www.vansairforce.com/community/showpost.php?p=869139&postcount=19

So maybe this is now specific to Bendix 1200s, what?s the preferred method of magneto side wiring.. thanks
 
Learned these connections are called P-Leads, with different types where some are grounded on both ends, some aren?t. Also learned different ways to do this with toggles to reduce the risk of having hot mags with a failed ground point. I also found that to test I need to disconnect them from the magneto plead post.

http://www.vansairforce.com/community/showpost.php?p=869139&postcount=19

So maybe this is now specific to Bendix 1200s, what?s the preferred method of magneto side wiring.. thanks
Having the mag fail hot is a good thing; it means that if the ground fails in flight, the engine keeps turning.
 
Having the mag fail hot is a good thing; it means that if the ground fails in flight, the engine keeps turning.

You're absolutely right, maybe I was missing something on the post I was reading. Either way looking to do just the conventional type of wiring on the Mags and can't seem to find any solid info or pictures.
 
To close this out here is what I found-



So in my case I need to remove the ACS ground from my ground tree. Go ahead and recrimp and solder sleeve new terminals to magneto end. Grounding sleeve to magnetos and ensure no threads mix with Plead.
 
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